Sprung vehicle seat

Abstract

A sprung vehicle seat has a base member and a top member, and a scissor support assembly operatively disposed therebetween. The scissor support assembly comprises first and second pivotably interconnected scissor levers. Secured to the first scissor levers is a sliding guide in the form of a plate member which is oriented in the longitudinal direction of the seat. A spring member bears against the sliding guide and the top member and is displaceable in the longitudinal direction of the seat for the purposes of weight adjustment of the seat.

What is claimed is:  
     
       1. In a sprung vehicle seat comprising 
       a base member,  
       a top member,  
       a scissor support assembly operatively disposed between the base member and the top member and comprising first and second lateral scissor levers each having a first fixed end and a second movable end remote from the first end,  
       a scissor support assembly pivot means pivotably movably connecting the scissor levers together,  
       a sliding guide mounted to the first scissor levers and oriented in the longitudinal direction of the seat, and  
       a spring means having first and second ends and co-operable at the first end with the sliding guide displaceably in the longitudinal direction of the seat on the sliding guide for weight adjustment of the vehicle seat,  
       the improvement that the sliding guide is in the form of a plate member which in the non-loaded condition of the vehicle seat is oriented at least approximately parallel to the top member,  
       a first slide member carried on the plate member slidably in the longitudinal direction of the seat for fixing the first end portion of the spring means, and  
       a second slide member at the underside of the top member slidably in the longitudinal direction of the seat for fixing the second end portion of the spring means,  
       wherein the first and second slide members are connected together by the spring means and are thus displaceable simultaneously in the longitudinal direction of the seat for weight adjustment of the vehicle seat.  
     
     
       2. A vehicle seat as set forth in  claim 1   
       wherein the spring means is formed by a conical spiral spring which increases in width from the first end portion to the second end portion thereof, and  
       wherein the first slide member has a holding projection adapted to hold the first end portion of the conical spiral spring and the second slide member has a collar adapted to hold the second end portion of the conical spiral spring.  
     
     
       3. A vehicle seat as set forth in  claim 1   
       wherein said plate member has a main portion extending in the longitudinal direction of the seat forwardly in relation to the scissor support assembly pivot means towards the fixed end of the two lateral first scissor levers, and a secondary portion extending rearwardly in the opposite direction away from said pivot means.  
     
     
       4. A vehicle seat as set forth in  claim 3   
       wherein at least one of said main portion and said secondary portion of the plate member has an abutment operable to bear against the base member when the vehicle seat is in its lowest condition.  
     
     
       5. A vehicle seat as set forth in  claim 1  including 
       a flexible non-stretchable member tensioned between said first end portion and said second end portion of said spring means.  
     
     
       6. A vehicle seat as set forth in  claim 1  including 
       a pre-loading spring member operatively disposed between said base member and said top member.  
     
     
       7. A sprung vehicle seat comprising 
       a base member,  
       a top member,  
       a scissor support assembly operatively disposed between the base member and the top member and comprising first and second lateral scissor levers each having a first fixed end and a second movable end remote from the first end,  
       a scissor support assembly pivot means pivotably movably connecting the scissor levers together,  
       a sliding guide in the form of a plate member mounted to the first scissor levers and oriented in the longitudinal direction of the seat, the plate member in the non-loaded condition of the vehicle seat being at least approximately parallel to the top member,  
       a first slide member carried slidably on the plate member in the longitudinal direction of the seat,  
       a second slide member at the underside of the top member slidably in the longitudinal direction of the seat, and  
       a spring means having first and second end portions, the first end portion being fixed to the first slide member and the second end portion being fixed to the second slide member,  
       the arrangement being such that the first and second slide members are connected together by the spring means and are thus displaceable simultaneously in the longitudinal direction of the seat for weight adjustment of the vehicle seat.